New Delhi: A day after Avinash Chander was removed as chief of the top defence research organisation, Congress General Secretary Digvijay Singh Wednesday demanded that the government explain its decision.

"Avinash Chander DRDO Chief dismissed 15 months before his term expired. Would Government please explain?" he tweeted.

The Appointments Committee of Cabinet headed by Prime Minister Narendra Modi had "approved the termination" of the contract of Avinash Chander with effect from January 31.

Chander, who was Secretary, Defence Research and Development cum Director General, DRDO and Scientific Advisor to the Defence Minister, retired on November 30 last on attaining 64 years of age and was given a contract for 18 months till May 31 next year.

The removal of Chander after being given a contract had raised questions over the Government action.

Chander had joined DRDO in 1972 after completing graduation in Electrical Engineering from Indian Institute of Technology (IIT), Delhi.

Chander is known to be the chief architect of Agni series of ballistic missile systems.